A122577 - OEIS

%I #15 Dec 18 2022 07:04:22

%S 1,1,7,10,1,169,21,2,1801,144,1,39202,521,1,275807,3194,1,6625109,

%T 6765,2,70602821,46368,1,1536796802,167761,1,10812186007,1028458,1,

%U 259717522849,2178309,2,2767771787041,14930352,1,60245508192802

%N A nonsense sequence.

%t a[1] = {2, 2}; a[2] = {2, 1}; a[3] = {1, 2}; a[4] = {1, 1};

%t M[n_] := If[Mod[n, 3] == 0, {{ 0, 1}, {1, 2}}, If[Mod[n, 3] == 1, {{0, 1}, {1, 1}}, {{0, 1}, {1, 0}}]]

%t v[n_] := v[n] = MatrixPower[M[n], n].a[1 + Mod[n, 4]]

%t a1 = Table[v[n][[1]], {n, 1, 50}]

%K nonn,uned,less

%O 1,3

%A _Roger L. Bagula_, Sep 17 2006